Driving mechanism for vehicles



June 5, 1951 H. B. GRANGROTH ETAL 2,555,881

DRIVING MECHANISM FOR VEHICLES Filed Aug. 19, 1948 2 Sheet's-Sheet 1 Z5/arr? 5. 'mngmih Lawrence @Lean/2f Joe JVOZZ ZZOI a @M June 5, 1951 H. B. GRANGRo-rl-l E-rm. 2,555,831

DRIVING MECHANISM FOR VEHICLES Filed Aug. 19, 1948 2 Sheets-Sheet 2 Patented June 5, 1 951 DRIVING MECHANISM FOR VEHICLES Harry B. Grangroth, Lawrence D. Leach, and Joe B. Noll, Minneapolis, Minn., assignors to Le Jay Manufacturing Co., Minneapolis, Minn., a firm Application August 19, 1948, Serial No. 45,114

Our invention relates generally to propelling or driving mechanisms, and, more particularly, to a power driving mechanism adapted to be attached to vehicles, garden implements, and the like.

A highly important object of our invention is the provision of a driving mechanism which can be quickly and easily attached to a vehicle to be driven Without necessitating structural changes in the vehicle. y

Another object of our invention is the provision of means for attaching the drive mechanism to a vehicle wherein said means may be easily adjusted to vehicles of various widths.

A still further object of our invention is the provision of a drive mechanism having closelyspaced axially-aligned ground wheels, the tires of which cooperate to form a V-pulley whereby the ground Wheels are driven.

Another object of our invention is the provision of a novel clutching arrangement incorporated in the driving connections between the motor of our device and the ground-engaging drive wheels thereof.

Another object of our invention is the provision of a drive mechanism as set forth which is inexpensive to build, which is easily attached to an implement such as a lawn mower or the like, and which is rugged in construction and efficient and durable in use.

The above and still further highly important objects and advantages of our invention will become apparent from the following detailed specication, appended claims, and attached drawings.

Referring to the drawings, in which like characters indicate like parts throughout the several views:

Fig. 1 is a View in perspective of our novel driving mechanism attached to a lawn mower;

Fig. 2 is an enlarged front elevation of the machine of Fig. 1, some parts being broken away and some parts shown in section;

Fig. 3 is a transverse section taken substantially on the line 3-3 of Fig. 2;

Fig. 4 is a fragmentary section taken substantially on the line 4--4 of Fig. 1;

Fig. 5 is a fragmentary section taken substantially on the line 5-5 of Fig. 4

Fig. 6 is an enlarged fragmentary section taken on the line 6--6 of Fig. 4 and Fig. 7 is a View in perspective of our novel driving mechanism or attachment with the motor thereof removed and some parts broken away.

Referring with greater detail to the drawings,-

3 Claims. (Cl. 180-19) the numeral I indicates in its entirety a frame comprising a normally horizontally-disposed platform 2 having a pair of laterally-spaced flanges 3 depending therefrom adjacent the rear end thereof. The lower ends of the flanges 3 are slotted as indicated at 4 to receive a sha-ft 5 on which are journalled a pair of driving wheels 6. The opposite ends of the shaft 5 are diametrically-reduced and threaded to receive washerequipped clamping nuts 'I which, when tightened, clamp the shaft 5 in the desired position in the flanges 3. The wheels 6 are each provided with a pneumatic tire 8 and are disposed in an axiallyspaced relationship wherein the side walls of the tire 8 abut one another. In this relationship, opposed side faces 9 of the tire 8 cooperate to form an annular V-groove I il, which functions as a V-pulley for a purpose which will hereinafter become apparent.

We provide means for attaching the frame to a wheeled vehicle, such as a lawn mower, said means being in the nature of a pair of tubular arms II and I2. Said arms II and I2 extend transversely of the frame I and are each rigidly secured to the platform 2 forwardly of the ground wheels 6 by means of clamping plates E3 and nutequipped bolts I4. The arm II is axially-aligned with the arm I2 and has rigidly secured to its inner end, by means of welding or the like, an axially-projecting rod I5 which is telescopically received in the inner end portion of the arm I2 (see particularly Figs. 2 and 3). At their outer ends, the arms I I and I2 are bent to form radially-extending portions I3 which are provided with apertures II. The apertures Il are adapted to receive handle-mounting trunnions I8 usually found on conventional lawn mowers. In the drawings, the lawn mower is indicated in its entirety by the numeral I9 and includes ground Wheels 29, revolving cutter element 2|, cutter blade 22, and roller 23. A Cotter pin 24 prevents the trunnions I8 from becoming disengaged from the apertures I1. The arrangement immediately above described permits attachment of our novel drive mechanism to mowers or vehicles of different widths. This is accomplished by merely removing the handle of the mower, loosening the clamping plates I3, and moving the arms II and I2 transversely of the platform 2 until the trunnions I8 are received Within the apertures I'I. The clamping bolts III are then tightened whereby to maintain the arms I I and I2 in the desired position. It will be noted that the arms II and I2 may be rotated when the clamping screws I4 are loosened so that the radially-projecting ends of the arms II and I2 may be raised or lowered to the height of the trunnions I8.

A bearing bracket 25 is rigidly secured to the rear end portion of the platform 2 by means of bolts or the like 26, and has journalled therein a jack shaft 21. The jack shaft 2'I preferably overlies .and is parallel with the drive wheel shaft 5. The kshaft 27 extends axially outwardly of both ends 'of the bearing bracket 25 and has fast on one projected end thereof a relatively large Ipulley 28 and at its other projected end a relatively small pulley 29. A motor or internal combustion engine 35 is mounted fast on the forward end of the platform 2 .and has secured fasi'l on the drive shaft 3l thereof a pulley 32. The pulleys28 and 32 are preferably of the V-type and have running thereover a V-belt 33. It will be noted by reference to Fig. that the bolts 26 pass u pwardly through a slot 2.5 in the platform 2 to enable the bearing bracket to be shifted toward and away'frcm the engine 3 0 so that the V-belt 33 may be maintained under proper tension.

Running over the relatively small V- pulfley 29 and the V-groove lil formed by the Opposed side faces 5 of the tires is a V-belt 3d. The length of the belt til and the spacing of the `pulley 29 and tires 3 is such that the belt SLi-normally runs very loosely over `the pulley 29 and V-groove Iii. In fact, the looseness of the belt 34 permits the pulley 25 torotate Iwithout engaging the b elt'S-to drive thesame. Obviously, and as shown in Fig. 4, the pulley 2.9 lies in a plane extending Vtransversely through the shaft 5 intermediate lthe wheels 5 and Ythe belt Sil passes through a rectangular opening 35 in the platform 2.

Provision is made vfor causing 'the `V--belt 3@ to operatively frictionally engage the pulley 29 and V-grcove Iii as follows: A handle bar 35 is bifurcated at its lower end and-hinged-ly @0K1- nected to the flanges 3 of the frame vI as indicated at 3'?. The handle bari inclincs rearwardly from the frame i and terminates at its upper end in a pair of hand grips 38. YIntermediate its ends, the handle bar 35 has secured thereto, by welding or the like, a transversely-extended sleeve 35 in which is pnfotally secured p intle pin or shaft A rigid link si! is transversely slidaole 'in one end portion of the shaft 45 and is held against sliding movements therein by a set screw or the like ft2. The .link lli extends forwardly and downwardly 'to a point slightly forward and below the ,pulleyrt where it is bent at a right angle to form a stub shaft .43. An idler pulley iii is journalled on the stub shaft43 and lies in the plane of the pulley .239 and the VV.-

groove i0, and, as shown in Figs. l and '1, ,lies partly 'within the aperture 35 of the platform .2. It will be seen by reference to the full line position in Fig. l of the handle bar 35 that the belt Sil loosely engages the pulley 2.9. When .the handle bar is moved to its dotted-line position of Fig. l, the idler pulley tl is moved r-.earwardly by the link di whereby to take-up the slack in the belt Eli and cause-it -to operatively engage the pulley 25 and the opposed sidefaces $3 of the tires 8. A coil tension spring e5 Ah as one end anchored to the bearing bracketZE, as findicated at li, and its yother end secured to the sleeve 3 9, as indicated at Ll?. The spring 4 5 biases the handle bar 35 toward its full lineeposition of Fig. .l to antoine ticallydecrease-or eliminate altogether ,frictional engagement of the pulley ,.29 .with the belt lflence moving of the handleahar i6 toits dotted linenositionrof,

Fig. 1 must be accomplished against bias of the spring 45 and the handle bar 36 must be held in the lowered position for the duration of the operation of the drive. Obviously, when it is desired to stop the vehicle it is but necessary for the operator to release his hold upon the hand grips 3 8 whereby to allow the bias of the spring 45 to pull the handle bar 3B to its full line position of Fig. 1 and move the idler pulley 44 out of tightening engagement with the V-belt 34. r:Phe proper :amount of slack to be initially imparted to `the belt 35 is determined by the position of the shaft 5 with respect to the jack shaft 21. A s seen in Fig. 4, this adjustment is made by merely moving the wheel-mounted shaft 5 upwardly or downwardly in the slots d and clamping the ,same in the desired position by tightening the nuts l.

Our novel attachment has been found to peri to any other vehicle, such as .a small wagonfor` f sled.

While .we have shown and described Y,a single embodiment of our device, it will be understood that the same is capable of modification without departing vfrom the spirit and scope of theinvention as defined in the claims. V

What we Claim is:

1. In a device of the class described, a supporting frame adapted to receive a motor adjacent its frontend, a pair of .closely-.spaced axiallyaligned pneumatic tire-equipped ground Vwheels adjacent the rear end of said frame, ,a transfversely-disposed jack shaft journalled on said frame, driving connections from said `n iotor vto said jack shaft, a pulley on said jack shaft, said pulley being in a vertical .plane extending 'transversely of the axis of said wheels Vand intermediately thereof, a belt running overV saidpulle'y and opposed side faces of said tires., meansasSiOciated withsaid frame forwardly of s aid ground-wheels for securing said Vframe to a wheelrequi'ppedve.- hicle, a Vrearw ardly-inclined handle ibarfpivotally secured-at its lower end to said frame, andmeans associated `Ywith said handle bar for inoreajs'l'ig frictional contact between said beltandsaidpulley and tires when said handle bar is pivotally moved in one direction and decreasing ,frfi contact of said -belt with said .pulley and when said handle .bar is vp'ivotally moved Athe opposite direction whereby to allow said pulley ,to rotate .independentlyof -said ground wheels."

2. vIn a deviceof the class described,a. support ing frame adapted to receive a motor adjacent its .front end, a p air of closely-.spaced axiallyaligned pneumatic tire-equipped groundfwheels adjacent the rear end of said frame, a tlaIlSF versely-disposed jack shaft journalled .on said frame, driving connections from `said ,to said ,jack shaft, a pulleyonsaidjack s haftsaid pulley being in a vertical plane extending transversely of lthe axis. of .said `wheels and intermediately thereof, a belt running over ,said pulley and opposed sidefaces .of .said tires, means associated with said frame forwardly. of-saidfground wheels for securing said frame to ,a wheelequipped vehicle, a rearwardlyeinlined Ehandle bar lpivotally mounted at itsflower end to. said frame, arigidlink having one .end pivotedtofsaid handle .ber .intermediate the @ads iibseof, idler ,pulley Y:Joiirlflalled to the .other @ed -efffaid 'link and adapted to engage said belt whereby to increase frictional engagement of said belt with said pulley and tires when said handle bar is moved in one direction and decrease frictional engagement of said belt with said pulley and tires when said handle bar is moved in the opposite direction.

3. The structure dened in claim 2, in further combination with spring means biasing said handle bar and idler pulley in a, direction to decrease rrictional engagement of said belt on said pulley and tires, whereby to allow said pulley to rotate independently of said ground wheels.

HARRY B. GRANGROTH. LAWRENCE D. LEACH. JOE B. NOLL.

Vil

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 460,375 Higgins et al. Sept. 29, 1891 1,357,396 Gater Nov. 2, 1920 1,461,716 Blackmore July 10, 1923 1,479,092 Springer Jan. 1, 1924 1,657,514 Miller Jan.. 31, 1928 2,066,174 Creger Dec. 29, 1936 2,070,288 Mack Feb. 9, 1937 2,151,659 Fenk Mar.. 21, 1939 2,238,707 Ronning Apr. 15, 1941 2,285,230 Robertson June 2, 1942 2,426,342 Couse Aug. 26, 1947 

